Variable volume balloon and method of its manufacture



VARIABLE VOLUME BALLOON AND METHOD OF ITS MANUFACTURE Filed July 13, 1950 W. F. HUCH Sept. 30, 1952 5 Sheets-Sheet 1 /SINGLE GORE PATTERN 3O GORES- H T w W M U m x A M F. o T m o P //VVEN7'0R.'- WILLIAM F. HUGH BY 7% Q Arranntr W. F. HUCH Sept. 30, 1952 VARIABLE VOLUME BALLOON -AND METHOD OF ITS MANUFACTURE Filed July 15, 1950 I 5 Sheets-Sheet 2 50 so /-v/vr0k:- WILLIAM F. HUGH 7% arrom'vn so GORES M m w w w w w w w w w w o w w M w M M w M M M a O Em. wmj z zoo m Z0 33 m o: It; 93th; 5; E 3 mi]? ZOO 12m Sept. 30, 1952 w. F. HUCH 2,612,328

VARIABLE VOLUME BALLOON AND METHOD OF ITS MANUFACTURE Filed July 13, 1950 5 Sheets-Sheet 5 I v F165 66 l 1;; I I 58 I llu l m (Q M m u\ l l 4 UH l I 54 l 32 )IVVE/VTORI- ILLIAM F. HUCH' BY ATTORNEY Sept. 30, 1952 w. F. HUCH 2,512,328

VARIABLE VOLUME BALLOON AND METHOD OF ITS MANUFACTURE Filed July 15, 1950 5 Sheets-Sheet 4 //vvE/vr0R.'- WILLIAM F. HUGH y 9444-; 0. El 4 A T TORI/E Y Sept. 30, 1952 w. F. HUCH 2,612,328

VARIABLE VOLUME BALLOON AND METHOD OF ITS MANUFACTURE Filed July 13, 1950 s sheet's-sheet 5 INVE R; WILLIAM F. HU

BY arren/15y Patented Sept. 30, 1952 VARIABLEVULUME BALLOON AND METHOD OF ITS MANUFACTURE William F. .Huch, St. .Paul, Minn., assignor to General Mills,"lnc .,'a corporation 'of Delaware upp icanonsuly13,:1950, Serial No..'17:3620

Claims.

.1 This application relates .to balloons aandsmore particularly to :high altitude balloons :capable of carrying a substantial-payload.

*High altitude for stratosphere rballoons :are -.already known in which the balloon :bodyiis made up of a large number of :vertically extendin gores :or lunes joined to .each :other .:at their adjacent edges to .form- :a .gasproof bag. Such a.

balloon is shown-.ifor example in United .States Patent-$526,719 which-is. assignedto the assignee of the present inventiom In the:;design .of .such balloons-pit "has been previously considered essential 'that at :least the upper portion of thelballoon beo'f spherical shape. 'Thezparticular typeshown v in the abovementionedpatenthas a spherical upper portionywhile the lower portion of the .balloon is. in the form of a cone tangent :to the: lower portion of the sphere.

In the manufacture of such balloons, because of the relatively large sizes involved, it .has been been desirable to form the individual .gores or lunes -by means of a pattern, the shapeof which is computed =so1that apredetermined number. .of

such gores, when joined to each :other :atitheir longitudinal adjacent-edgesywill form a balloon body" of the desired shape; The size of these gores,and*-the patternby-which they areform'ed,

are chosen to yield a balloon-body of predetermined volume which will-lift the expected paye load to the desired predetermined 'altitudei -1Al+ titudes of theorder of 100, 000 feet or more-have been achieved by balloons of the general type 7 described.

Ordinarily, balloons of thistype are designedv for maximumhigh-altitude performance} There are oce'asions', however, when it is desirable in the course of upper ai-r' research to provide a balloon which will remain fora substantial. pe-- riod of timeat-a somewhat lower altitude; Since previously it has been considered essential "to have the upper portion of the balloons spherical, it has accordinglybeennecessary to construct a balloon of the same shape, but of smaller size. In other words, the individual gores would be similar to those of the higher altitude balloon but-wouldbe smaller in all respects.

Where these goresare being made and assembled on a pattern or gore table of the type shown.

in the -copending application of La Mere, John son, andWinzen, Serial No. 18,585., :filed April 2, 1948, it was necessary to construct a new pattern or tablarforv each balloon of different desired volume'andj altitude. performance. Because of the size of the individual-gems the construction 01' such separate patterns is extremely expensive and time consuming. It has" therefore not been .economicalto providefor flights at a number 16: I I

appreciably different altitudes.

Other attempts have been made to obtain-- flights at altitudes substantially below that for wh1ch "the balloon is originally .designed. For example, it has been-suggested that the payl ad be increased in order to hold the .balloon at a lower level. The strength of the balloon -however, sets a limit to the decrease in altitudewvhich is possible by increasing the payload-inthismam ner. The change ineffective altitude may ;be as little as :6 to. 10,000feet by doubling or tripling a load. Such an attempt'also increases thes tresses on the balloon body .and therefore can"not b e carried beyond the point at which thematerials,

of the balloon will withstand the added (strains. Another suggestion which has been made isto use a gas which is somewhatheavier than that for which the balloon is designed but which is Ordinarily these balloonsf still lighter than air. are designed for use with helium. The number of other possible gases available is extremely llmi-ted and their general explosive quality zandunavailability make this method of obtaining,

lower altitude flights impractical. Y

There has been a further suggestion that the helium used in such a balloon be diluted with air or other gases. This method .is successful for moderate reductions in desired altitude. However, the amount of, air required to dilute the:

helium rises exponentially with .thexdecreasea-in:

/ altitude'so that the use of .thismethod-is unsatisfactory where substantial reductions are :desired. With these defects and problems of the prior art in view, it is accordingly one object of. the

present invention to provide an improvedhi h altitude balloon. Another object .is the provision of "an improved process for the manufacture of high altitude "or stratosphere balloons.

A still further object is the provision .of azproB ess of balloon manufacture in which a single gore pattern can .be "utilized to produce balloons of different predetermined volumes and shapes in order tov achieve flights at different :predetermined altitudes.

Another object is the provision of a process-of v balloon manufacture in which a gore pattern is designed to provide a balloon having-a substa-n:

tially spherical portion and in which provision. 1s made for the utilization of the same-gorepattern 1n the manufacture of balloons llaving -aj smaller volume than that for which the: gonads originally designed. H

K sou another objectis the provision; of} germiproved method of makingand capping-a'balloohu.

of substantially smaller volume than that for which the gore pattern is designed.

A further object is the provision of a balloon capping process in which a long, spindle shaped balloon body is formed by seaming together a lesser number of gores than the predetermined number required to obtain a balloon having a spherical portion and in which the balloon body is capped by a conical member formed from the major sector of a circle of predetermined characteristlcs.

Other objects and advantages will-be apparent from the following specification in which a preferred embodiment of the invention has been described with particular reference to the accompanying drawings. In these drawings,

Figure 1 is a side elevation showing the shapes of a family of variable volume ballons made according to the invention.

Fig.2 is'a plan view of a single gore for use in the manufacture of any of the variable volume balloons of Fig. 1.

Fig. 3-is an enlarged partial viewof thegore or gorepattem illustrating one method of determining-the-shape of a gore required to obtain a spherical balloon portion when a predetermined number of such gores are united.

Fig. 41s a composite graph showing the relationship between-balloon volume, balloon weight, and altitude with 110 pound payload of balloons of one typical variable volume family having dif ferent predetermined numbers of gores.

Fig; 51s a partial perspective view showing details of a conical balloon cap and the method of '4 which are illustrated at 32-4 and 322 in Fig. 1. These gores are preferably made of light thermoplastic material and are seamed to each other at their adjacent longitudinal or vertical edges to form a balloon body 20 of the desired shape when a predetermined numberofsuch gores have been united. l a .4 1

Various methods for thedetermination of the exact shape and dimensions of the individual gores are available in the prior art. Fig. 2 illustrates a single gore or gore pattern and indicates that this gore has a portion of maximum width at 34 which tapers in both directions toward the upper end 36. and lower end 38 of the pattern.

Since the balloonbody 20 is symmetrical about I its verticalaxis 46, which latter constitutes an axis of revolution, it is preferable that the individual gores 32 also be symmetrical with respect to their longitudinal or vertical center line 40. Thus the two longitudinallyv extending gore edges 42 and 44 are spaced equally on each side of the center line Eli and taper. smoothly. toward the center line at 36 and 38 from the point of maximum width 34. v I Since the particular balloon 20 which is illustrated'includesa conical lower portion iinstead of being a completely perfect sphere, it will be apparent that the portion of vthe'gore 32 from the point of maximum width 34 towardthe top 36 will differ both in length andexactshape from the gore portion between the point of maximum width 34 and the bottom 38 of. the pattern. Should a spherical balloon be desiredgthese upper and lower gore portions would bethe same.

Fig. 3 illustrates one method by which the exact gore dimensions can be determined atany point from the point of maximum width 34 toward that end of the gore which corresponds to the balloonv portion for which a spherical shape isdesired.

gas seal and sealing together of the capped por tions. I Fig. 8 is a view similar to Fig. 7 showing the conical cap fully in position and with its longitudinal edges secured together. v I Fig. 9 shows a subsequent step in the capping process with certain of the desired load bearing tapes superimposed above the cap and the load bearing seams and tapes of the body portion.

Fig. 10 illustrates the application of the load bearing tape at the very apex of the cap.

Fig. 11 shows the manner in which this apex first designed. Such a balloon is illustrated at 20 inFig. 1. In accordance with the teachings of the prior art, one preferred form for this balloonlil of maximum performance includes a spherical upper portion indicated at 22 and a conical lower portion 24. The conical lower portion is tangent to the sphere along a substantially horizontal circle at point 26. The balloon 20 is designed to have a plurality of load lines 28 attached at its lower end for the suspension of a payload 36.

' Theballoon body itself, in accordance with the teachings of the above-mentioned patent, is preferably formed of a plurality of vertically or longitudinally extending gores or lunes 32, two of In the determination .of this gore pattern the first step is to decide the size of the balloon body which is desired, this size being, dependent upon the payload to be carried andthe altitude to be reached. In the ballooon body 2i] of Fig. 1, the

spherical upper portion 22 of the balloon will have its center 48 located at some point on the vertical axis 46 of the balloon body. The upper spherical portion of the balloon 20 is indicated as having a radius R from the center 48 of this portion. In this particular case the center 48 will lie in a-horizontal planecorresponding to the 2 When the radius R of this spherical portion has 5 been determined, and when the number of desired gores has been decided upon, the design of the individual gore pattern can be started byj computing, the maximum width of the gore at point 34. In this case, for convenience, the dimension atthis point. of maximum width has been shown as the dimension of ahalf gore, i. e.,

the distance from the center line MLto either of the symmetrical edges 42 .and 44. Thus the method of computation to be illustrated herein, can be used satisfactorily whether the gore pattern or table to be used corresponds toacomplete gore as in the above La Mere, Johnson,; and

the formula width 34 is determined by max ,T

where Rl' -is the desired radiiis of thef spheric'ali portion of thefballoon arid n is thed'esired num ber-of gores to beused forsuch aballoen; Thus 12. willbe a'whole number.

Where the balloon is relatively large, or. where it is desired that the balloon shape: very closely approximate a sphere, without substantial deviations due to the face that the-gores are made'of flat material which is substantiallynon elastic; a relatively 'large'number of gores will be utilized.- Thus in the balloon shown' -atill in Fig; 1,-foi' purposes of illustration it is assumed that 60 gores tare'iinvolve'd.

II'i- Eig.I 3} the distance of 'any oth'er 'p'ortion of the: gore :edges 42- and 44" from thelongitudinal center-line :40 can' be determined according to-"the followingformula:

wherezRcand'tnt have the' same values as above and where s. is .the distance Falongthe .center'line 40 from the point of maximum .width' at 34'to-the point-atwhich the width We isdesired.

-It is; apparent in this expression. that l W: will equal .zero when the; distance 1rR I sequels. i. e ,when. s correspondsto the length ofv arc" of onequarter of a greatcircle of a sphere having R as its radius. Thiswould bethe pointof in-.-.' tersectionofthe gores 32 with the vertical-axis 46 of balloon 20 in Fig. 1. 7

In actual practiceit is difficult-to scam the goresto -each other at I this apex of the balloon if each gore does tapercompletely-to. zero and if. the: distance s does increase to the full maximum represented by the distance It is therefore customary. to make the gore slightly, shorter than required so that-the upper. end 36 ofLthe g' ore will have a finite width. Thusthe balloon body formed by uniting. a plurality. of such gores will have a small substantially circular openingatit's apex. This opening must then be capped in some manner. In the case of a-spherical'balloon' portion, themethod oi capping, is preferably/that shown in the above-mentioned patent.' When the balloon body portion is non-- spherical, as in the case of certain of the other variable volume balloons madeaccording to the process'fof. the present invention, then a diiferent capping method and cap must be-employed, for example the capand method described-in the: later portions ofthis specification.

It-should .be noted that the actual value-compute'd "for the distance W5 according to the-above formularepresents an approximation, since-this formula yields the distance from the center line of the gore to one of its edges as measured alongv a :parallel, i.e'., along the arc of intersection between thesurface of the resulting sphere and a plane. perpendicular to the vertical axise46. Where thenumber of gores is relatively large, the formula can be used satisfactorily. On the other hand"where"tli'number of'gores n is relatively small, the; value of the expression W's may, be

furtliercorreceted or refined by the use of addi.- 70-" tional formulas. For most purposes, however, a gore pattern in which ithe'dimensions are determined substantially according to the above formula-,2 will .yieldaa"spherlcal balloon portionof the desired radiusiRn. 1,

patternasillustrated-in Figs. 2 and 3. 'Ihebal- "*loon whosev shape is represented at 50- is one'win the balloon 20. At the same-time the balloon 50;.

6 As' indicatedfl aboveit has='-"been ;g'ner ai1 thought and-"definitely taught in the 'prior that-flights at lower altitudes than that fomwhic the balloon 2 0 w'a's designed} would 'have to b obtained in one of the methods-discussed nth introductory portions of this specification} he by increasing the payload,-by using-aheavier' gas than that for which the ballooncwasde-y signed; .by diluting the: originally intended gas-' withnainor by redesigning the" ballocn on a sm'allenscale' so that the same' effective spherica v shape-f0" theupper portion'of the b lloonwoul'd" be maintained but' the individual gores would b shorter I and narrower sosthat the resulting b loon would have smaller predetermined v'oluni' According? to one feature'of the-present in vention', I have found that itis possible to 1 pro duce'a' ballooniof desired lesser-volumethan tha of the balloon 20," for example; by usingthe sam gore pattern illustrated in Fig 2! anddesigiited in'accordance with the'sp'ecifi'cati'onsoiTFig and seaming together: the longitudinal edges of a number of gores which is substantially less th'a the number n which was used .in computation o the individual gore pattern. In other words-sac cording to the present process, a gore pattern i first designed so'that' 'a predetermined number n of gorescorresponding to the pattern T wille when united, produce a balloon havinga desiredpredetermined volume and shape; .When dlf' ferentiperformance characteristics arerdesi-red; ai plurality ofgores representedby" the number fl'n will be seamed together; where :z:"'is:a':numb'e substantially different. from= n. Dependingi 'on -i the shape of gore originally designed" and the shape of the'balloon resulting therefrom; itisu; possible that as might be either=greaterrors smaller than n. In the present case,rhow'ever, Where v the gore pattern isdetermlnedin such .%a fashion that n gores will yield aballoon' having a? spherical portion at least atone'end, then nrep-aresents the maximum number of gores'ordinarily'ii used,v while at may be substantially"lesssthan nah Generally, a: would be chosen somewhere. sub-p, stantially within the range between v and n in this preferred form of balloon;.-- Since the particular gore pattern illustrated in. Figs. 2 and 3 is designed to yield a bBJIQOHQZUM havinga spherical upper portion 22 as shown {121 Fig. l-when the predetermined number'of eores g are joined, it willbeappav entlthat the seaming:

together of a lesser number of gores will :yield. a balloon body which is nonspherical at its upper portion. Fig. 1.-i1lustrates the shapes, asseen in side elevation, of two other balloons-of thevari-j, able volume family-made from the same. gore= which 40: instead of 60 gores have been seamed. together, The maximum width 'or circumference: ofthisballoon is substantially less than thatyof is som'ewhat longer or higher. Thus the "general:- effect of reducing the number of gems in this form of the invention'is toiyield a more spindle shaped or longer and narrower balloom The balloon shape indicated .at-52 represents the-casewher'elll goresinstead ofthecoriginallyn designed 60, have been seamed together. This; particular,balloonis; even longer i and-narrower thanuthe zballoonzio; Asxindicate'd above; it isioridinarilymreferable thatrthenumberiofegoresauseda cu. :ft. ,5;while a balloon of 30 sores has besomewhere between one-third of the :number which wouldyield a spherical shape and the m me beryitself. The two cases illustrated represent one-half, respectively, of n.

Figured is a composite graph illustratingceringthoseshown in Fig. 1', which are made with differentnumbers of gores corresponding to. the

, the cases. where :1: equals two-thirds and rcequals 1 1 mm; characteristics of various'balloons, includthe vertical .axis. In curve A, the graph reprehasavolume of roughly-225,000 cu. ft. A balloon of-.-.'10..gores has a volume of just under 100,000 aLvoldme of theorder of 55,000 cu. ft

CurveiB of Fig. 4. illustrates the relationship thezsamegore pattern, the weight of each gore I will bet-tthesame and therefore this relationship is-linean- The balloonzwelghts shown for 60, 40,

, sentsgthe volume in cubic feet of the finally resuiting. balloon plotted against the number of gores employed. Here it will be noted that a 60 goreballoonoorresponding to. shape 200i Fig. 1.

I between.;balloon"weight and number of' gores v since-zeach of the gores is made to correspondto between the number of gores and the altitude which-can be expected with a 110 pound payload ontheballoon? Thus the 60 gore balloon is illustrated as approaching the 100,000 ft. altitude,

j while the 40 and gore balloons are suitable-for use at altitudes of substantially 82,500 and 72,500

ft.:, respectively.

Obviouslythe specific values shown and illustrated in Fig.4 will depend in any given caseon the particular; balloonshape and balloon volume for which. the indivldual'gore pattern is designed. The values will also depend on the type of mate- 1 marily for purposes of illustration, to establish the fact that a wide range of performance characteristics can be achieved according to the methods of the'present invention with the use'of a.

single'gore pattern of predetermined size and shapef'For a given gorepattern, it is only necessary to know the performance characteristics which'are desired in the finalproduct and toselect a number of gores which will yield a balloon having the desired characteristics.

As pointed out above, when the balloon has the spherically shaped upper portion for which thegores are ordinarily designed, it may be made and'capped in the manner of the above patent.

As described in that case, the balloon itself is' made of polyethylene or similar material having low temperatures. The individual gores are preferably seamed to each other at their adjacent edges by. a heat sealing or welding operation which forms a seam 33 of the. same material in-' 'tegrally connecting the adjacent gores.

Overlyinglthe seamsbetween adjacent gores area plurality-of load tapes 54 as shown in Figs. 5-12, in-

clusive.

. thede'sired flexibility and other characteristics after prolonged exposure to ultraviolet light and According tothat prior patent, the ballooncap 1 waseformed of a circular piece of similar thermoplasticzmaterial applied tothe top opening and taped thereto in a specified manner."- This, capping'operation' is suitable for use wherethe upperportion of the balloon is substantially flat as in the case of the top or pole ofa relatively large spherical portion.

In the present invention, however, there are cases where the number of gores is substantially less thanthe number required to yield a flat area at the point of intersection of the gores, and in such cases it is necessary to provide a diifere'nt capping means and method. According to the invention the cap is formed from a piece of thermoplastic sheet material similarto that from which the balloon bodyis formed, the cap being cut in fiat form in: the, shape of a majorsector of predetermined characteristics.

fiat material can be joined to each other and thereby form a cone from the sector of material, the angle of inclination of the walls or elements of the cone being determined by the numberof degrees in the central'angleincluded between the radial edges of the sector.

In the present case, in the form of invention where the gore pattern is chosen so that ngores will yield a balloon portion of spherical shape at its apex, a satisfactory conical cap 58 may be made by taking a sector of a circle as illustrated in Fig. 5. The center of the circle is indicated at 60. The two'radii which bound the i sector are shown at 63 and 64, and the circular are which completes the sector is shown at 62. The radius of the sector, i. e., the'distanc'e from the center 60 to the arc sz'is so chosen that the center 60 canlie at the point at which the edges of the'individual gores 32 would intersect thevertical centrala-xis of the balloon and would intersec't each otherif the gores were tapered completely to a point. 1

As indicated above, however, the upper ends of the gores are of finite width so that a top opening 56 is left in the balloon body. Thus the center'lill of thecap 58 is located ati'substantiall'y what would have been the point of intersection of the gore edgesj This is substantially the point at which a line tangent to the gore. seain adjacent theopening wouldintersect the vertical axis of the balloon and opening. The radius from point '60 to the are 62 of the-cap is great enough so thata substantial area of the cap ,willoverlapaporresponding area around-thefopening at the upper end of the balloon body. The length of the radial edges of the sector, or'theslantheight of the cone formed from such sector is accordingly substantially greater than the radius of the top opening. Similarly, the length of the arcuate edge of the sector, or the circumference at the base of the resulting cone, is substantially greater than the circumference of the opening. H

To provide means for the formationof a conical cap ;from' the sector 58, a flap fitiisjprovided at one of theradii bounding the, sector,

in this case along the radius 54.. The angle68 between the'radial edges 63 and .64 of the sector 58 has a definite and distinct relationto the number of gores used, where the goreswere originally designed to produce a spherical balloon portion when n *gores were connected. The

sion

where rc'isthe: number of gores" actually used and n is the number which would-yield a'spherf- It knownv that the radial edges defining a-given sector of size of this angle is. determined bythe expres- I gas seal is completed at the thirtieth gore. that remains to be done to complete the gas seal 7 .is to apply one or two additional tapes (10 and fold down the'fia'p 64 adjacent the free edge or cal section and for which the gore pattern was designed. In Fig. a...30- gore balloon is illustrated and since the gores were designed for a '602 gore Iballoon having the shapeshown at 20 in Fig. l, the value ofuangletli .is one-half of I ';-360 or 180; 1

The method by which the sector as is applied to the: balloon body'zand'formed into a conical cap is illustrated in Figs. 5-12, inclusive. The first step in the process is to lay out the upper end of the balloonlbody on a fiat area substantially as shown in Fig. 5 and to apply the cap with the'desired overlap'as shown by the heavy line portions of Fig.5. The edge'or radius 63 "of :the cap is preferably aligned with one of the .egore seams; i. a, with the seam and-load beari-ng tape 54 at one'edge of. the gore 32.--l. -the1alignment has been completed ,astshown in Once Fig.5, the cap 5Bis folded. over from the heavy line to "the dotted line=position of the figure so that the first'of a series of gas sealing members or tapeslfl may be applied. As .shown' in Fig. 6, "the gas seal is formed'by short lengths of tape having a pressure sensitive adhesive on one sur- :face.. "These tapes are placed on the inner "side'of the gores 32,I, 32-4, etc., at the upper edge of the balloon, with the sticky side of the itape facing'outwardly so that good adherence "Willa-be. obtained with :the inner surface of each gore and also with the inner surface :of the balloon"cap 58.w Because of the'shape of opening 5.6"at'the top-of the balloon body and because of the .difliculty .of handling the pressure s-sensltive'tape large lengths, a plurality of relatively shorttapes 10 are used-as shown in Fig. 6 and are substantially overlapped to provide the necessary seal and strength.

After the gas seal is initiated at the region near the first radius '63 of the cap, theapplica- -tion of, the gas'seal ,iscontinued along the upper edges of the gores.

As the gas seal tapes are applied, more and more of the capping mem- -ber 58 is folded back over fromthe dotted line qpositionof 5 toward the heavy line position.

At the same time-the balloon body of Fig. 5 is shiftedxso. that in. the particular application shown the upper portion or layer of the body is moved from right to left while the lower section is moved fromleft to right.

Fig.- '7 illustrates the situation just before the radius of the cap. A reenforced bleed opening "IZ' n ay be provided in thecap at this time according .to the teachings oftheabove'patent to prevent destruction of the balloon cap and its fastenings due to expansion of air between the ber. V W shown in Fig. '8', anaddition'al series of All .edge ,of the conical cap .58 ,overlaps. thelgqx ing tapes 18 are also provided with,

. ping' portions of the cap and body a 'thepeak of the cap end heaeeeeges 82 shaped upperportion hasfnot pre sponding to a single pattern accordingly controlled high altitude 'fiights' at'a W1 .nection between the cap and ball QnJqQd the cap due to air currents.

the. application of a series of loadbear tion, and overlap the load .bearin the balloon body. Tapes 18 are appl e ,84 in Figs. mend ,11. j

persons skilled in this field, 'it i 1. Themethod offfor ing mint ie'i o steps. of forming ,a plurality of gores 3.2. Tapes 16 increase the strength of ,thej'c'on prevent any. peeling action on .the

The final step in the completion 6t was illustrated in Figs. 9-12. Th

sitive adhesive, in a preferred"forn1 'of t point on tapes 54 substantially b ellow .and are extended up along "the lt 'pes 54 seams 33 of the balloon body, across the apex of the conical cap: Atthe upper end '80 of the tape extends li'ghtl are folded down on the cap as shown upper .portion of theballoon body It: pwhen all ,of the top load bearing tapes 18 h 'e been ap V It .has been foundin practi shaped balloons with a conical v applied according to the presentin uflicient strength to accomplish the ject of the invention and tpf p tory performance at relatively even though the use'of such a co'n'ic possible to accomplish the objects set f' beginning of the specification an i of difierent predeterminedaltitudes with extra expense and time required for the p tion'of a different gore pattern or bal for each different altitude desired.

Since minor variations and changes act details 'of' construction], wil

{this invention shall cover all such "modifications as fall within thesp of the attached claims)" 4 'Now ,;therefore,I'claimzf" the pattern, seaming-oneedge of affi edge of the second gore,successively edge of each additionalgore to th free edge of the preceding gore-emu seaming 'gether the remaining free edges of the first and last gores at a time when "the tot'al numb of united gores is different trdm 's'aidpredetenm ried number. 2. The method of forming multiple 01 8121331- loons of different volumes and shapes iwith the aid of a single .goreapattermdesigned tosprovide a balloon having a. spherical portion when spredeterminednumberzof gorescorrespon'd-ing o the pattern are united, .;which' comprises-the of =ta'pe's'of the' pressure'sensitiveadhesive be'may applied at 16" at the point --where the lower;

- .forming a plurality of goresaccordingtto thema tern, seaming onenedge o'fi azfirsle sqrez caotcdse amases edge of the preceding gore, and seaming together 'the remaining free edges of the'first and last a 11 a 1'2 of theisecond gore, successively seaming one edge of each additional gore to the remaining free where R is the radius of a spherical balloon portion of maximum desired volume and n is a pregores, at a time when the total number of united 5 I v'gorleslfis less than said predetermined number. determined Whole number n in whmh the gore Thm th d successively forming multiple shape between the point of maximum width and ballad-n57 of different volumes and Shapes at least one end of the gore is determined subthaivd of a Single gore pattern of definite stantially according to the formula:

I predetermined .shape which comprises the steps TR 8 180 of forming afirst balloon by (a) forming a plu- 'IE' 1.-

8 1s Ithesec'o'nd gore, (c) successively seaming addi- 1111.6 from the ofmaxtmum wldth toward .vltion'al gores to the remaining free edge of each saw n W5 15 the Wldth from h gore preceding gore, and (d) after a predetermined center line to the goreedgg theft dlstfame number of gores have been seamed to each other, and and n are the same. a formmg seaming together the remaining free edges of the mummy gores correspongmg to sald 5 patfirst and last gores thereby com p1 eting a first tern, seammg one longitudinal edge of the first balloon body of desired volume and shape, and gore lopgfltudmal edge. of the Second gore forming ar -second balloon by following steps (a), mi addltlonal gores wlth i of each an and .v (a) above and then seaming together additional gore seamed tothe remaining free edge the remaining free edges of the first and last of the preceding gore, unt1l a total of x-gores have -gores at a time when the total number of seamed been wmediwhere a: Is whole less than gores is different from said predetermined numand Seammg together the remammg edges br thereby ,completinga second balloon body of of the first and last gores thereby completing diflrht-vo'mme-and Shape; L balloon body of desrredvolume i 4. The method of formingmu1tip1e gore The method according to clalm 8 in which lbufis. 6f differentvolumes and shapes which a; is chosen substantially 1n the range of values. .lzrl mak s Single gore pattern f a gore v ig g hg riei d according to claim 8 in com-- hfi figr g lfifi z fi l lgg zgiffgzg i g bination with the additional steps of forming a Y bo th ends and which when a predetermined bane-on Pap m the shape of a Sector of a V nfimfier orgores c rre spo g to the pattern cirgle1 n21 wh1ch tclire central angle between the adness seamed together at adjacent longim 6 g boun mg the sector equals ;tudinal 'edges, is designed, to provide a balloon 0 body of predetermined volume with a spherical n portion at least at one end of its axis; forming a V gammy of gores corresponding to said pattern; Seahngtthearcuate i of the sector to, the dand seaming together at their adjacent longi- 40 gg fi seahng tog-ethane 'tud'inal edges a number of gores substantially less 22 re ges 0 6 Sec or to complete a conrmal than said predetermined number, thereby form- .i ng a balloon body of smaller volume with aconifi fi accqrfimg to 01mm m cal portion at said one end instead of said spherima Ion W e addmonal steps of formlgg call portion. 1 V V flat balloon cap in the shape .of a sector of a circle 5; The method of formingmumple gore in which the central angle between the radial cloons of ifierent volumes and shapes which comedges bqundmg the sector equals m prises making a single gore pattern for a gore x o v hi h has a. maximum transverse width equal to 5 1/11, timesthe maximrun circumference of a desired balloon having predetermined Volume and sealing the arcuate edge of the sector to the gores T shape, where n is a Whole number forming a at said one end, sealing together the radial edges rams: gores corresponding to said pattern; and of i Sector 1 complete, a conical a and u g x gores at their. adjacent longitudinal hesively securing a plurality of load bearing tapes edges to form a balloon body of differ to the cap, with one tape overlying each of the fumeand shape, where a: is a whole number other Seams between adlacent gores and extending h than n. 1 M I from the gore seam over the cap to the top of 6. The method according to claim 5 in which a: sapld comcal is less than n, and in whichthe gore pattern is The method of cappng substantially stormed tbvpmvide'abaubon of ngores which has completed balloon body having a circular top the shape vof a hemisphere from the region of Whlch campuses forming fiat balloon maximum circumference to at least one end. cap m the Shape of a sector of circle in which i -The method according to .claim 6 in which the lengi-ih of the arcuate edge Pf the Sector is the gore pattern is -formed to provide a balloon sub-Manually the Samevas the clrcumfemnce 0f .Ofh gates which hag i shape defined v y 5 a c1rcular area of the balloon body enclosing the pheie a due end and a cone a ge to the top opening and 1n wh1ch the length of the radial 4 V a edges of the sector is greater than the radius of l P11 lhat$1h%g1glf2formmg balloons of different said circular area; securing the arcuate edge of V J .i r J I the cap to the circumference of the circular area;

. volumes dg h y fron l, a plurallty of gores -7 and thereafter securing. together the radial edges which are each symm r Wlth respect to a of the sector and thereby forming a conical cap longitudinal' center line, which comprises makabove id j ing asingle' gore-pattern in which'the maximum 13. A high altitude balloon having a spindlewidtli from-the longitudinal center line of the .shaped upper body portion comprising a plurality littgorejtorone edgegof the g q l of vertically extending gores of gas proof material seamed together the cap top.

at their adjacent edges, the upper ends of the gores defining a top opening in a given horizontal plane, with the seamed gore edges immediately adjacent the openin being inclined upwardly toward a predetermined point on the. central vertical axis of the balloon spaced substantially above the plane of said-opening, and aiconical' cap member having a "base edge which is secured to the body portion around the edge of the opening with the apex of the a conical cap being located at said predetermined point. a .L

14. A balloonaccording to claim 13 in which a load bearing tape'j is adhesively securedto the balloon body at each gore seamand extendsover the conical caplto the top thereof, the upper end of the tape having its corners folded-down and overlappingly secured to each other and 15. The method of capp a substantially completed balloon body having a circular top opening which comprises forming a flat balloon cap in the shape of a sector of a circle in which the length of the areuate edge of the sector is substantially the same as the circumference of a circular area of the balloon body enclosing the top opening and in which the length of the radial edges of the sector is greater than the radius of said circular area; securing the point of in tersection of the arcuate edge and one radical 1 edge of the cap to the circular area of the balloon bodyadjacent the opening; successively securing the remaining portions of the arcuate edge of the cap to the circumference of the circular area; and thereafter securing together the radial edges of the sector and thereby forming a conical cap above said opening.

WILLIAM F. HUGH.

REFERENCES CITED The follbwing" references are of record in the file of this patent: v

UNITED s'ra'm's, PATENTS OTHER REFERENCES Atkins: "Practical Sheet and Plate jdetal Work." page 102, 82. 

